WASHINGTON - With debate intensifying in the United States over the use of drone aircraft, the U.S. military said on Sunday that it had removed data about air strikes carried out by unmanned planes in Afghanistan from its monthly air power summaries.

U.S. Central Command, which oversees the Afghanistan war, said in a statement the data had been removed because it was "disproportionately focused" on the use of weapons by the remotely piloted aircraft as it was published only when strikes were carried out - which happened during only 3 percent of sorties. Most missions were for reconnaissance, it said.

The debate over the use of drones in Afghanistan and elsewhere was triggered in part by U.S. President Barack Obama's decision to nominate his chief counter-terrorism adviser John Brennan, an architect of the drone campaign, as the new director of the CIA.

The Air Force Times said air force chiefs had started posting the drone data last October in an attempt to provide more detail on the use of drones in Afghanistan.

The University of Missouri's journalism school is the oldest in the country and now among the first to experiment with the new -- and controversial – drone technology. NBC's Thanh Truong reports.

The newspaper said the statistics were provided for November through January, but the February summary released on March 7 had a blank spot where the drone data had previously been listed.

"A variety of multi-role platforms provide ground commanders in Afghanistan with close air support capabilities, and it was determined that presenting the weapons release data as a whole better reflects the air power provided" in Afghanistan, Central Command said in its statement.

"Protecting civilians remains at the very core of AFCENT's (Air Force Central Command's) mission," it said. "The use of all AFCENT aerial weapons are tightly restricted, meticulously planned, carefully supervised and coordinated, and applied by only qualified and authorized personnel."

The statement said the decision to stop reporting the drone strikes was taken with the International Security Assistance Force - the NATO-led coalition in Afghanistan.

Brennan was sworn into office on Friday following a protracted confirmation battle that saw Senator Rand Paul attempt to block a vote on the nomination with a technical maneuver called a filibuster, in which he tried to prevent a vote by talking continuously.

Paul held the Senate floor for more than 12 hours while talking mainly about drones, expressing concern that Obama's administration might use the aircraft to target U.S. citizens in the United States.